KFLOP User Manual 2021 Table of Contents KMotion/KFLOP Executive Software Screens Bode Plot Screen Page 4 GCode Screen Page 13 Page 15 KFLOP Axis Configuration and Page 18 C Program Screen Parameters IIR Filter Screen Page 27 Configuration/ FLASH Screen Page 33 Step Response Screen Page 46 Console Screen Page 55 Axis Screen Page 57 KFLOP Board specific Summary Page 58 Quick Start/USB Driver Installation Page 59 HW/SW Specification Page 66 Board Layout Page 68 Block Diagram Page 70 Hardware/Connector Description Page 71 Analog IO Screen Page 81 Digital IO Screen Page 84 Page 90 Virtual COM Port Driver Page 91 Functional Diagram Installation General Servo Flow Diagram Page 106 Driver Library Routines Page 107 Script Commands Page 119 Driver Library Flow Diagram Page 202 Using Multiple Boards Page 203 Preemptive Multi-tasking Page 205 RS232/UART Page 206 .NET Interface Page 210 KMotionCNC KMotionCNC Page 211 G Code Viewer Screen Page 226 G Code Viewer Setup Screen Page 228 Tool Setup Screen Page 230 Page 256 Control KMotionCNC from Page 266 TP Corner Rounding KFLOP 1 | P a g e KFLOP User Manual 2021 MCodes with Parameters Page 269 Geo Correction Table Page 270 Embedded/Buffered IO Page 264 Page 279 Spindle Control Commands Fiducial Alignment Page 289 Using Multiple Configurations Page 292 Mach 3 Mach3 Plugin Page 294 Mach3 Encoder Setup Page 306 Mach3 G31 Probe Setup Page 313 Passing DROs Page 317 Mach3 Rigid Tapping Page 318 KStep Hardware Specification Page 323 KStep Connector Pinouts Page 324 Block Diagram Page 337 Board Layout Page 338 KStep Use and Settings Page 339 KStep Basics Tutorial Page 351 Kanalog Hardware Specification Page 376 Kanalog Connector Pinouts Page 377 Block Diagram Page 386 Board Layout Page 387 Kanalog Use and Settings Page 389 Konnect Hardware Specification Page 393 Konnect Connector Pinouts Page 394 Block Diagram Page 402 Board Layout Page 403 Software PWM to Analog Page 404 Example SnapAmp SnapAmp Use and Settings Page 411 SnapAmp Connector Pinouts Page 415 SnapAmp Plotting Example Page 422 2 | P a g e KFLOP User Manual 2021 KNozz Summary Page 429 Hardware Specification Page 430 Connector Pinouts Page 431 Block Diagram Page 437 Page 438 Converting a milling machine to Board Layout a 3D printer (link to wiki article) Examples Step/Direction Output Mode Page 439 Brush Motor/SnapAmp Example Page 450 Closed Loop Step/Dir Output Page 465 Page 472 Resolver as User Input Mode Mode Data Gather Example Page 481 Videos Step and Direction Page 483 Brush Motor with SnapAmp Page 483 Resolver with KMotion Page 483 Nonlinear Kinematics Page 483 IR Remote Control Page 483 KSTEP 4-Axis Stepper Amp Page 483 Our videos on YouTube Page 483 Forum/Support Dynomotion Forum Page 483 CNCzone Forum Page 483 Dynomotion Wiki Page 483 Copyright © 2005 - 2021 [DynoMotion]. All rights reserved. Revised: 01/21/2021 3 | P a g e KFLOP User Manual 2021 Bode Plot Screen The Bode Plot Screen allows the measurement of a servo loop and graphs the open loop response. A Bode Plot is by far the most common means used to measure and understand the behavior of a control loop. KMotion contains advanced built-in features to allow rapid Bode Plot measurement and display. The current PID and IIR Filter transfer functions may also be superimposed and graphed. A Bode Plot is a plot of magnitude and phase of a system with respect to frequency. Any linear system that is driven by a sinusoidal input for a long time, will output an sinusoidal signal of the same frequency. The output signal may be shifted in phase and of a different magnitude than the input. A Bode plot is a graph of both the change in phase and the relative change in magnitude (expressed in decibels, db), as a function of frequency. A Bode plot is a useful tool used to examine the stability of a servo feedback loop. If a system has an open loop gain of -1 (magnitude of 0 db and phase of -180 degrees), then if it is placed into a negative feedback loop, it will become unstable and oscillate. Because a system's gain and phase vary as function of frequency, if the system has a magnitude of 0db and phase of -180 degrees at any frequency it will be unstable and oscillate at that frequency. The way to avoid an unstable system is to avoid having simultaneous conditions of 0db and -180 degrees occur at any frequency. Where the magnitude of the system is 0db the amount that the phase is different from -180 degrees is called the phase margin. The larger the phase margin the more stable the system. Similarly where the phase is 4 | P a g e KFLOP User Manual 2021 -180 degrees the amount that the magnitude is different from 0db is called the gain margin. Again the larger the gain margin, the more stable the system. As a general rule of thumb, for a system to be reasonably stable it should have a phase margin of at least 30 degrees and a gain margin of at least 3 db. The Bode Plot Screen attempts to identify and measure the 0 db crossover frequency (the first point where the open loop magnitude becomes less than 1, often defined as the system bandwidth, 228 Hz on the example above), the gain and phase margins, and one or two sharp peaks in the magnitude data after the crossover. Some mechanical systems have sharp resonant peaks that may cause the system to go unstable if these peaks approach the 0 db line and have phase near -180 degrees. A notch filter placed at these frequencies may increase performance. The measurements are displayed under the graph as shown below. The most direct method for obtaining the open loop response is to break the servo loop open, inject a signal into the system and measure the output. However, this is usually impractical as most systems will run out of their linear range if driven in an open loop manner. KMotion operates the servo loop in its normal closed loop form, injects a command signal, measures the position response, and mathematically derives the open loop response. This does require that the servo loop function in some form as a stable closed loop servo before a measurement may be made. Performance is not a requirement so low gains might be used to obtain an initial stable system. 5 | P a g e KFLOP User Manual 2021 To perform a Bode Plot Measurement: select the channel to measure, select the desired Amplitude and Cutoff Frequency for the stimulus to be injected, select the # of samples to average, and depress the Measure Pushbutton. All current Configuration Parameters (from the Configuration Screen), Tuning Parameters (from the Step Response Screen), and Filter Parameters (from the IIR Filter Screen) will be downloaded, the selected Axis channel will be enabled, and the measurement will begin. While the measurement is in progress the number of samples acquired will be displayed and the Measure Pushbutton will change to a Stop Pushbutton. Pushing the Stop button will stop acquiring data after the current sample is complete. Depending on the type of plot requested (either Time Domain or Frequency Domain) either the last acquired time domain measurement will be displayed or the average all the frequency domain measurement so far acquired will be displayed. Unfortunately Bode Plots often have regions that are very noisy. But fortunately these are almost always in regions that are not important to us. At frequencies where the open loop gain is very high (usually at low frequencies), the servo loop performs very well, and the Position closely matches the Command signal. In this case, the calculation of the Error signal (see above) is calculated by taking the difference between two nearly equal values. A small error in Position measurement will then result in a relatively large error in the calculated error value. Similarly, when the system has a very low gain (usually at high frequencies), the position signal is very small and often highly influenced by noise, or if an encoder is used, by encoder resolution. The regions of interest in order to determine system stability, are where the open loop gain is near 0db and the measurements are normally very accurate. Additionally, instead of injecting sine waves at various frequencies individually, KMotion uses a technique where a random noise signal that is rich in many frequencies is injected. Using a method involving an FFT (Fast Fourier Transform) of the input and output, the entire frequency response may be obtained at once. Bode Plot analysis is fundamentally based on the assumption that the system being analyzed is linear. Linear in this context means that any signal injected into a system that provides a response, might be broken into parts, each piece injected separately, and all the resulting responses when summed would equal the original response. If a system being measured does not meet this criteria then the 6 | P a g e KFLOP User Manual 2021 result is basically useless and meaningless. Masses, Springs, Dampers, Inductors, Resistors, Capacitors, and all combinations thereof are examples of devices which produce very linear effects. Static friction, Saturation, and Encoder count quantization, are examples of non-linear effects. It is therefore very important to verify that while the system is being measured that it is operating in its linear range. This usually entails that the system isn't being driven too hard (or too fast), so that the drive to the system (Output) is not reaching saturation. Additionally, it is important to verify that the system is being driven sufficiently hard (or slowly enough) that a measurable Position change is being observed.